Question

A bullet (m=20g) shot with a speed of 800 m/s hits an oak tree and sticks 4cm inside it.

What is the average force acting on the bullet from the tree?

Answer 1

Hi there!

We can begin by converting cm to m:

4cm = 0.04 m

Use the following equation:

vf² = vi² + 2ad

The final velocity is 0 m/s, so:

0 = vi² + 2ad

vi² = -2(a)d

Plug in given values to solve for the acceleration:

800²/2(0.04) = -a

a = -8,000,000 m/s²

Find the force using the equation:

F = ma

F = (0.02)(-8,000,000) = -160,000 N